Extech Instruments MO257 User manual

Brand: Extech Instruments

Model: MO257

Category: Measuring, testing & control

Type: User manual

User's Guide

Pinless Moisture Meter

Model MO257

MO257-en-GB_ v1.4 5/16

Introduction

Congratulations on your purchase of the Extech MO257 Pinless Moisture Meter. The pinless

moisture sensor monitors the moisture in wood and other building materials without causing surface

damage. High frequency sensing technology allows the meter to take non-invasive moisture

measurements. User programmable alarms alert the user if moisture measurements exceed alarm

set-points. This meter is shipped fully tested and calibrated and, with proper use, will provide years of

reliable service.

Meter Description

1. Measurement sensor

2. Power ON-OFF button

3. LCD display

4. Measure (MEAS) button

5. UP and BACKLIGHT button

6. SET button

7. DOWN button

Battery compartment located on rear of unit

LCD Display

1. Low Battery icon

2. Main LCD display

3. MAX reading

4. MIN reading

5. HOLD function

6. Measurement alert

7. MAX mode icon

8. MIN mode icon

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Battery Replacement

1. Turn off the meter

2. Remove the Philips head screw located on the rear of the unit

3. Lift off the rear battery cover

4. Replace the three (3) ‘AAA’ 1.5V batteries

5. Secure the rear battery cover

Never dispose of used batteries or rechargeable batteries in household waste.

As consumers, users are legally required to take used batteries to appropriate collection

sites, the retail store where the batteries were purchased, or wherever batteries are sold.

Disposal: Do not dispose of this instrument in household waste. The user is obligated to

take end-of-life devices to a designated collection point for the disposal of electrical and

electronic equipment

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Operation

Pinless Moisture Measurements

1. Press the power button to turn the meter on.

2. As described below, you must calibrate the meter before first use.

3. To calibrate, press the MEAS button immediately after powering on the meter. The display will

audibly beep and visually flash the CAL display icon. Keep the measurement sensor at least 3

to 4” (8 to 10 cm) from any object during calibration.

4. When the calibration is complete the beeping and flashing stop. The calibration reading must

not exceed 0.5. If so, re-calibrate ensuring that hands or other objects are kept clear of the

measurement sensor.

5. The meter should be calibrated whenever it is moved from one measurement area to another.

6. To take a measurement, hold the meter and position the sensor so that it is very near or

directly touching the surface under test. The meter can sense moisture to a depth of 0.79 to

1.57” (20 to 40mm).

7. IMPORTANT NOTE: The position of the hand can greatly affect a reading. Do not move or

reposition the hand that holds the meter while taking measurements or when calibrating the

unit.

8. The LCD indicates a relative moisture reading in numeric digits from 0.0 to 100.0 and with

programmable alarm alerts (DRY, RISK, and WET).

9. Press the MEAS button to HOLD (freeze) a reading on the LCD (the HOLD icon will appear on

the LCD). The meter will hold the reading for 30 seconds before automatically shutting the

meter down.

10. The MAX and MIN display areas indicate the highest and lowest readings encountered since

the measurement session was started.

11. If the battery symbol appears or if the meter does not switch ON, replace the batteries.

Alarm Settings

Two high alarm points can be set for Moisture measurements: A RISK Alarm (0 to 50 setting range

with a default setting of 30 units) and a WET Alarm (50 to 100 setting range with a default setting of

60 units).

Moisture Alarm Setup Procedure:

1. Press the MEAS button to place the meter in HOLD mode to change the Alarm settings.

2. Press the SET button. The RISK display icon will appear flashing on the LCD indicating that a

RISK alarm can now be programmed.

3. Use the up/down buttons to select the desired RISK Alarm value.

4. Press the SET button when the desired setting is displayed.

5. The WET icon will appear flashing on the LCD indicating that the WET Alarm is ready to be

programmed.

6. Use the up/down buttons to select the desired Wet Alarm setting.

7. Press SET to complete the programming.

8. Now, if the moisture measurement is higher than the RISK setting, the meter will beep once

every two seconds and if the moisture measurement is higher than the WET setting the meter

will beep four times per second.

9. Press the MEAS button to exit HOLD mode.

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Auto Power Off

To conserve battery energy, the meter will enter a sleep mode after approx. 30 minutes of inactivity.

Press the power button to wake the meter.

Backlit LCD

Press the up/backlight button to switch the backlighting ON or OFF.

Specifications

Function Range Accuracy

Moisture Range 0.0 to 100.0 Relative only

Measurement Depth 20 to 40mm (0.79 to 1.57”)

Display type Backlit LCD

Display digits Three (3) numeric displays; each displaying from 0.0 to 100.0

Display icons HOLD, DRY, RISK, WET, MIN, MAX and low battery icon

Operating Temperature 4 to 43°C (40 to 110°F)

Operating Humidity 90%, 0-30°C (32-86°F), 75%, 30-40°C (86-104°F),

45%, 40-50°C (104-122°F)

Power Supply Three (3) 1.5V ‘AAA’ batteries

Auto Power Off (APO) After 30 minutes of inactivity

Dimensions 235 x 63 x 28mm (9.2 x 2.5 x 1.1”)

Weight 218g (7.7oz)

Moisture Comparison Table (typical)

Material Display units Moisture status

Gypsum < 30 DRY

30 - 60 RISK

> 60 WET

Cement < 25 DRY

25 - 50 RISK

> 50 WET

Wood < 50 DRY

50 - 80 RISK

> 80 WET

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Extech Instruments MO257 User manual

Brand: Extech Instruments

Model: MO257

Category: Measuring, testing & control

Type: User manual

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Extech Instruments MO257 User manual

Extech Instruments MO257 User manual

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